Mayahuelin, a Type I Ribosome Inactivating Protein: Characterization, Evolution, and Utilization in Phylogenetic Analyses of Agave

Abstract

Agaves resist extreme heat and drought. In A. tequilana var. azul, the central spike of the rosette-containing the shoot apical meristem and folded leaves in early stages of development-is remarkably heat tolerant. We found that the most abundant protein in this organ is a 27 kDa protein. This protein was named mayahuelin to honor Mayáhuel, the agave goddess in the Aztec pantheon. LC-MS/MS analyses identified mayahuelin as a type I RIP (Ribosome Inactivating Protein). In addition to the spike, mayahuelin was expressed in the peduncle and in seeds, whereas in mature leaves, anthers, filaments, pistils, and tepals was absent. Anti-mayahuelin antibody raised against the A. tequilana var. azul protein revealed strong signals in spike leaves of A. angustifolia, A. bracteosa, A. rhodacantha, and A. vilmoriniana, and moderate signals in A. isthmensis, A. kerchovei, A. striata ssp. falcata, and A. titanota, indicating conservation at the protein level throughout the Agave genus. As in charybdin, a type I RIP characterized in Drimia maritima, mayahuelin from A. tequilana var. azul contains a natural aa substitution (Y76D) in one out of four aa comprising the active site. The RIP gene family in A. tequilana var. azul consists of at least 12 genes and Mayahuelin is the only member encoding active site substitutions. Unlike canonical plant RIPs, expression of Mayahuelin gene in S. cerevisiae did not compromise growth. The inhibitory activity of the purified protein on a wheat germ in vitro translation system was moderate. Mayahuelin orthologs from other Agave species displayed one of six alleles at Y76: (Y/Y, D/D, S/S, Y/D, Y/S, D/S) and proved to be useful markers for phylogenetic analysis. Homozygous alleles were more frequent in wild accessions whereas heterozygous alleles were more frequent in cultivars. Mayahuelin sequences from different wild populations of A. angustifolia and A. rhodacantha allowed the

Integrated Transcriptome and Proteome Analysis Provides Insight into the Ribosome Inactivating Proteins in Plukenetia volubilis Seeds

“…At the initial stage, however, 3 RIP genes were expressed at higher levels. The results of our study corroborated the previous findings obtained by Llediad et al [ 44 ] and Loss-Morais et al [ 22 ] who reported that the expressions of members of the RIP gene family were often tissue-specific and developmental stage-specific. In addition to being specifically and highly expressed in seeds, Unigene0000172 also had higher expression levels in stem and stem apex.…”

Transcriptome Mining Provides Insights into Cell Wall Metabolism and Fiber Lignification in Agave tequilana Weber

“…Although the biosynthetic pathways for cellulose and lignin have been explored in A. sisalana , A. fourcroydes , and the hybrid H11648 [ 17 , 19 ], our study dissects both routes in A. tequilana for the first time, and provides their transcriptomic landscapes in contrasting tissues and organs for gaining more insights into the biological significance of the predicted orthologous. Variation in the numbers of isoforms found in both metabolic routes between our results and earlier analyses may reflect species or tissue-specific expression patterns, expressed according to the physiological status, development, and environment tested, as reported previously in Agave species [ 12 , 19 , 53 ]. For example, in silico expression profiling and qPCR assays of genes of the glycoside hydrolase family 32 revealed new vacuolar invertase isoforms only for A. tequilana and A. deserti but not for A. victoriae-reginae , and A. striata [ 12 ].…”

“…For example, in silico expression profiling and qPCR assays of genes of the glycoside hydrolase family 32 revealed new vacuolar invertase isoforms only for A. tequilana and A. deserti but not for A. victoriae-reginae , and A. striata [ 12 ]. Immunolocalization of mayahuelin, a type I ribosome-inactivating protein (RIP), showed differential protein abundance, including absence, depending on the Agave species or cultivar screened [ 53 ]. Several studies support the idea that CESA genes belong large families in monocots.…”

Evolutionary ecology of Agave: distribution patterns, phylogeny, and coevolution (an homage to Howard S. Gentry)

“…The most extreme case is A. tequilana , for which there is no genetic variation in tequila plants from Jalisco in the industry‐associated plantations, as reported by Gil‐Vega et al (2001), using 130 RAPD loci, a total of 40 plants, 10 plants per locality. These commercial A. tequilana plantations appeared to be a huge clone, representing a single genotype of A. angustifolia or of A. rhodacantha (Lledías et al, 2020). But in other less‐managed tequila populations, different levels of genetic and morphological variation and divergence have been detected.…”